I'm sorry to hear this and I'm sorry to say, but your mother is beyond reason and beyond saving. She obviously had some issues in her life and she grasped the straw of faith to save her. Now, because of that, her life is ruined, her children do not want to have anything to do with her, she will probably never meet her grandchildren. She can thank all that to her religion and her fundamentalist beliefs.

Unfortunately, she will die blaming the Devil for this, when it was God and her twisted view of God that ruined her life, not Devil.

My suggestion for you and your sister is to let go of your mother. Remember the good times, if there were any and forget everything else. It is a bad thing to say and a bad thing to do, but you have to choose between your life and your mother. If you continue to talk to her, you will continue to feel bad about her, you will bring back your old and bad memories over and over again, you will make compromises in your life for a person who does not want to budge a millimetre and continues to be selfish and do what she wants.

Love her and let go of her, live your life and make something worth doing. She cares for her Lord more than anything, including you and your sister, so let her live her life with the Lord.

Stay strong Sarah. Be strong for your sister and your nieces as well. Stick together, you are family and you need each other.

Peace.

I have a theory that the truth is never told during the nine-to-five hours.-Hunter S. Thompson

You are very brave. Catholicism is far to imbedded in the rest of my family parents siblings and nieces as it was in myself. I cut on the sneak and still pretend when I have to. I do believe that there are a few in there that are faking it but have the same fear that I do and that is being cut from a family I love. http://www.youtube.com/watch?v=jxo81Ok9Urk
I hope this youtube link works. It will make you break your sides with laughter.
Please tell me if you can't access it.